Method for obtaining test cores



March 30, 1965 J. R. D! STASIO 3,176,053

METHOD FOR OBTAINING TEST CORES Filed Oct. 50, 1963 INVENTOR. JOSEPH e.1

members be up to specification.

United States Patent ()fifice 3,176,053 METHOD FOR OBTAENING TEST CERESJoseph R. Di Stasio, 71h Shore Road, Spring Lake Heights, NJ. Filed Oct.30, 1963, Ser. No. 320,102 6 Claims. Cl. 26431) The present inventionrelates to method for the obtaining of test cores from bodies of setplastic material and the like, e.g., concrete floors in buildings orconcrete or macadam roadways.

Many structural elements are formed of plastic materials which arepermitted to set in place. Typical are roadways and floors and walls ofbuildings, and particularly multiple dwellings, office buildings andpublic buildings such as schools. The strength of the thusformedstructural elements depends upon many factors, including the particularclimatic conditions to which the structural members are subjected whilethe concrete or other plastic structural material is setting and aftersetting has taken place. Accordingly the only positive way ofdetermining the nature, and particularly the strength, of the setmaterial is to take a sample from the floor or Wall after the materialin question has completely set and subject that sample to appropriatelaboratory tests. The desirability of doing this is obvious,particularly because of the overriding importance, from a public safetypoint of view, that the strength of such structural Iowever, because ofthe difiiculty involved in removing a sample from a hard concrete massor the like, the conventional procedure is to pour a test cylinderseparate from the floor, and to take actual samples from the floor onlyin cases where the test cylinders indicate the possible existence oftrouble.

The removal of a test core from the hardened floor is accomplished bydrilling into the floor with a diamond tool after the poured concretehas been permitted to set for a length of time such as to permit it toassume its final physical characteristics. These operations are a sourceof considerable trouble and expense, not only because of the cost of theequipment needed to cut a core from a concrete floor or the like and thecost of replacement of the cutting elements themselves as they becomeworn out in use, but also because of the length of time required to cutthe cores from the floor, the latter representing a major factor ofexpense because of the high cost of labor. Moreover, since the concretecovers and hides the supporting surface and embedded reinforcing membersfrom view, the use of a diamond cutting tool frequently results in thecutting of the supporting surface or the reinforcements, an extremelyundesirable situation because of the reduction in the overall structuralstrength which results.

It is the prime object of the present invention to devise a method forobtaining test cores which eliminate the above disadvantages, and inparticular permit the obtaining of uniformly shaped and dimensionedcores in a simple and expeditious manner, and without in any wayadversely affecting the status of the cores as accurate and reliablerepresentations of the condition and properties of the remainder of theconcrete.

To these ends I provide a two-piece core-forming structure comprising anouter member and an inner member freely telescopically received withinand removable from the outer member. The outer member is mounted on thearea where the concrete wall or floor is to be formed, and the innermember is telescoped thereinto, the outer member having an open top topermit this action. Thereafter the concrete or other plastic settablestructural material is poured, that plastic material forming the wall oramass Patented Mar. 36, 1965 floor and also entering said inner member,which has an open top to facilitate the entry of concrete thereinto. 1cans are preferably provided to prevent the concrete from entering thespace between the inner and outer members. This means may convenientlycomprise an outwardly extending flan e on the inner member which restson the upper surface of the outer member, and which may also serve as asupport for the inner member when such support is needed. When, as ishere specifically disclosed, the inner member is provided with anaperture through which a punch may be passed to force the core from theinner member, means such as a plug may be utilized to close thataperture when the concrete is being poured into the inner member. Theconcrete is then allowed to set, and the concrete which defines the wallor floor and the concrete inside the inner member are both subjected tothe same pouring and setting conditions of workmanship, time,temperature, humidity and the like.

When the condition of the concrete is to be tested, the inner member isremoved from the outer member. This may very readily be accomplishedmerely by lifting the inner member out from the outer member, theaforementioned flange on the inner member conveniently serving as meansto accomplish this relative movement between the members. The setconcrete in the inner member defines the test core and may be subjectedto desired laboratory or held compression tests. It is usually desiredthat it be removed from the inner member before being tested. To thisend the inner member can be made of a disposable material and may bebroken away from the core, or the core may be driven out from the innermember, a portion of the bottom wall of the inner member being modifiedto permit this operation to be carried out. The space left inside theouter member when the inner member is removed can either be filled withconcrete, or that space can be used to house pipes or other elementsdesigned to penetrate the floor or Wall in question.

To the accomplishment of the above, and to such other objects as mayhereinafter appear, the present invention relates to the method for theforming and obtaining of test cores, as defined in the appended claims,and as described in this specification, taken together with theaccompanying drawings, in which:

FIG. 1 is a three-quarter perspective exploded view of the inner andouter members of the device of the instant invention;

FIG. 2 is a cross sectional view taken through a portion of a concretefloor and showing the manner in which the device is adapted to be used;

FIG. 3 is a cross sectional View taken along the line 3-3 of FIG. 2;

FIG. 4 is a three-quarter perspective view showing one manner in whichthe test core may be removed from the inner structural member;

FIG. 5 is a cross sectional view similar to FIG. 2 and showing oneprocedure which may be followed after the inner structural member andthe core which it contains have been removed from the floor; and

FIG. 6 is a cross sectional view illustrating the use of a plug to closethe bottom of the inner member when the thickness of the structuralelement is greater than the height of the inner member.

While in this specification mention is made specifically of theformation of a floor structure from concrete, this is by Way ofexemplification only, and it will be understood that the invention isapplicable to the obtaining of test cores from widely varying types ofstructunal elements formed of widely varying types of plastic settablematerials, the invention being applicable to all situations in which thetest core is to be accurately representative of the remainder of thestructural element.

The core forming apparatus comprises an outer member generallydesignated A and an inner member generally designated B which is adaptedto be telescopically received inside and removed from the outer memberA. The outer member A comprises a generally tubular shell 2 having anopen top 4 which is adapted to be mounted at any appropriate location ina formed structural element from which a test core is to be taken. Itmay be made of any suitable structural material capable of withstandingthe physical forces to which it may be subjected in use. Galvanizedsheet metal and cast or molded. plastic are typical of appropriatematerials. The shell 2 which defines the side walls of the outer memberA may be provided at its lower end with a plurality of apertured ears 6to facilitate the fixing of the outer member A in position. Thus, asshown in FIGS. 2 and 3, nails 8 may be driven through the apertures inthe ears 6 and into the supporting wooden structure 10 on which theconcrete floor is to be poured. While the cross sectional shape of theouter member A is here shown as circular, this is for convenience only,and any appropriate cross sectional shape may be imparted, provided onlythat the inner member B is readily receivable therein via the open top 4thereof.

The inner member B is defined by side walls 12, a bottom wall 14 and anopen top 16. It preferably has a flange 18 extending radially outwardlytherefrom at its upper end. The size and shape of the side wall 12 issuch as to permit the inner member B to be received inside the outermember A and to be freely removable therefrom. It is preferred that aclearance 2t) be pro vided between the side walls 12 and 2 of the innermember B and the outer member A respectively, in order to ensure readyinsertability and removability of the inner member B. The flange 18 isadapted to overlie, and preferably rest upon the upper edges of the sidewall 2 of the outer member A, thereby to substantially close the opentop of the clearance space 20 and, if the height of the inner member Bis less than that of the outer member A, to support the inner member Bin position. The height of the outer member A is preferablysubstantially the same as the desired thickness of the floor to beformed. The height of the inner member B is preferably the same as orless than that floor thickness.

With the inner member B positioned inside the outer member A, asindicated in FIG. 2, the concrete or other plastic material is poured,the mass 22 of the concrete which surrounds the outer member A definingthe floor whichis being formed. Concrete 24 also enters and fills theinner member B (see FIGS. 2 and 3).

After the concrete masses 22 and 24 have been permitted to set todesired degree the concrete mass 24, together with the inner member B,is removed from the floor, the mass 24 constituting a test core. Meansmay be provided in the exposed flange 18 to facilitate removal of theinner member B and the test core 24. Said means is here disclosed in theform of apertures 26 in line with the clearance space 20, through whichapertures 26 a simple hook may be passed, the thus engaged books beingemployed to bodily lift the inner member B out from the outer member A.It may be necessary to break away the flange 18 from the concrete 22surrounding it, and under certain circumstances, when a thin layer ofconcrete covers the flange 18, it may be necessary to break through thatthin layer, but this can readily and rapidly be done without having touse any special equipment.

Since it is usually desired that the test core 24 be subjected to testswithout any supporting structure therearound, means are provided topermit the test core 24 to be separated from the inner member B. To thisend the inner member B may be formed of disposable material, and maysimply be broken and stripped from the test core 24. Alternatively, andas here specifically disclosed, the side walls 12 of the inner member Bare either straight or provided with a slight upward and outward taper,and the test core 24 is adapted to be driven out of the inner member Bthrough the open top 1.6 thereof. To facilitate this latter operation,the bottom wall 14 of the inner element B may be provided with a centralopening 28 through which a punch 30 (see FIG. 4) may be driven.Alternatively the central portion of the bottom wall 14 corresponding tothe opening 28 may be weakened, so that the action of the punch 30 willseparate the weakened central bottom wall disk portion from the mainbody of that bottom wall 14 during the punching operation, the disk ofbottom wall material thus driven up by the punch 30 being stripped fromthe test core 24 after the latter has been separated from the innermember B. When, as is specifi cally illustrated in FIG. 6, the height ofthe inner member B is less than the floor thickness and the member B issuspended on the outer member A by means of la flange 18, a plug 31 ofwood or the like resting on the supporting structure 10 engages thebottom wall 14 of the inner member B and plugs or closes the opening 28,thereby preventing the passage of concrete through that opening. Inorder to reinforce the bottom wall 14 against the weight of the concretepoured into the inner member B, the plug 31, where it engages the bottomwall 14, is preferably substantially larger than the opening 28.

After the inner member B has been removed from the outer member A, thecontinuity of the floor may be recreated by filling the space inside theouter member A with concrete, as indicated at 32 in FIG. 5.Alternatively, the space inside the outer member A may be left empty,the outer member A thereafter functioning as a sleeve through whichpipes, wires, conduits or the like may be passed.

The inner member B may be formed of any suitable structural materialsuch as galvanized sheet material, aluminum, or suitable cast or moldedplastic. Those plastic materials having smooth surfaces are particularlypreferred, because the smoothness of such surfaces facilitates theseparation of the test core 24 from the member E as shown in FIG. 4.Alternatively, as illustrated in FIGS. 2 and 3, a liner 33 may beprovided within the inner member B, which liner may be formed of asuitable inexpensive material such as cardboard, the exposed surfaces ofwhich are preferably Waxed or otherwise treated to render them smooth,thereby to facilitate the removal of the test core 24 from the innermember B along with the liner 33, the liner 33 thereafter being readilystrippable from the test core 34.

The structural members involved are simple and inexpensive, and theinner members B, when not disposable, may be used a plurality of times.The saving in time and equipment, when compared with prior art methodsWhere the test cores are physically cut from the set floor, is fargreater than the cost of the parts involved in accordance with theteachings of the present invention, so that truly significantmanufacturing economies are realized. Through the use of the presentinvention truly representative test cores may be produced withsubstantially the same facility and minimal expense as characterizes theconventional formation of test cylinders separate from the floor.Moreover, since the test cores 24 set under precisely the sameconditions as the concrete masses 22 which make up the body of thefloor, the test cores 24 will be accurately representative of thecondition and physical properties of the actual floor material, thusfavorably differentiating over the prior art test cylinders.

While but a single embodiment of the present invention has been herespecifically disclosed, it will be apparent that many variations may bemade therein, all within the scope of the present invention as definedin the following claims.

I claim:

1. The method of forming a concrete test core from a concrete floor orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing within saidouter member an inner member having an open top and comprising r sidewalls, a bottom wall, and an outwardly extending flange at the upperportion thereof, said side walls being freely telescopically receivableinside said outer member, said flange extending radially outwardlybeyond the radially inner surface of said outer member and resting onthe upper edge of said outer member, pouring concrete over said areaaround said outer member and inside said inner member, permitting saidconcrete to set, removing said inner member, together with the concretecore formed therewithin, from said outer member, and removiug said corefrom said inner member.

2. The method of forming a concrete test core from a concrete door orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing within saidouter memher an inner member having an open top and comprising 'sidewalls, a bottom wall, and an outwardly extending flange at the upperportion thereof, said side walis being freely telescopically receivableinside said outer member,

said flange extending radially outwardly beyond the radially innersurface of said outer member and resting on the upper edge of said outermember, pouring concrete over said area around said outer member andinside said inner member, permitting said concrete to set, removing saidinner member, together with the concrete core formed therewithin, fromsaid outer member, and removing said core from said inner member and,after said inner member has been removed from said outer member, fillingthe space inside said outer member and permitting the filling materialto set.

3. The method of forming a concrete test core from a concrete floor orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing within saidouter member an inner member having an open top and comprising sidewalls, a bottom wall, and an outwardly extending flange at the upperportion thereof, said, side walls being freely telescopically receivableinside said outer member with a clearance space therebetween, saidflange extending radially outwardly beyond the radially inner surface ofsaid outer member and resting on the upper edge of said outer member,pouring concrete over said area around said outer member and inside saidinner member, permitting said concrete to set, removing said innermember, togeflaer with the concrete core formed therewithin, from saidouter member, and removing said core from said inner member.

4. The method of forming a concrete test core from a concrete floor orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing within saidouter member an inner member having an open top and comprising sidewalls, a bottom wall, and an outwardly extending flange at the upperportion thereof, said side walls being freely telescopically receivableinside said outer member with a clearance space therebetween, saidflange extending radially outwardly beyond the radially inner surface ofsaid outer member and resting on the upper edge of said outer member,pouring concrete over said area around said outer member and inside saidinner member, permitting said concrete to set, removing said innermember, together with the concrete core formed therewithin, from saidouter member, and removing said core from said inner member and, aftersaid inner member has been removed from said outer member, filling thespace inside said outer member and permitting the filling material toset.

5. The method of forming a concrete test core from a concrete floor orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing withinsaidouter member an inner member having an open top and comprising sidewails, a bottom wall, and an outwardly extendirig flange at the upperportion thereof, said side walls being freely telescopically receivableinside said outer member with a clearance space therebetween, saidflange extending substantially completely around said side wallsradiallyoutwardly beyond the radially inner surface of said outer member andresting on the upper edge of said outer member and closing the top ofthe clearance space between said outer and inner members, pouringconcrete over said area around said outer member and inside said innermember, permitting said concrete to set, remov= ing said inner member,together with the concrete core formed therewithin, from said outermember, and removing said core from said inner member.

6. The method of forming a concrete test core from a concrete floor orthe like which comprises securing in the area where said floor is to beformed an outer member which is open at its top, placing within saidouter member an inner member having an open top and comprising sidewalls, a bottom wall, and an outwardly extending flange at the upperportion thereof, said side walls being freely telescopically receivableinside said outer member with a clearance space therebetween, saidflange extending substantially completely around said side wallsradially outwardly beyond the radiallly inner surface of said outermember and resting on the upper edge of said outer memher and closingthe top of the clearance space between said outer and inner members,pouring concrete over said area around said outer member and inside saidinner member, permitting said concrete to set, removing said innermember, together with the concrete core formed therewithin, from saidouter member, and removing: said core from said inner member and, aftersaid inner member has been removed from said outer member, filling thespace inside said outer member and permitting the filling material toset.

References Cited by the Examiner UNITED STATES PATENTS 1,603,245 10/26Pederson 50-127 1,809,613 6/31 Walker 50-127 2,063,569 12/36 Walker50127 XR 2,644,220 7/53 Thaulow 26471 2,986,797 6/61 Aisenberg 2 64313XR 3,115,539 12/63 Stuessel et a1 50-127 XR 3,136,024 6/64 La Monica.

ROBERT F. WHITE, Primary Examiner. ALEXANDER BRODMERKEL, Examiner.

1. THE METHOD OF FORMING A CONCRETE TEST CORE FROM A CONCRETE FLOOR ORTHE LIKE WHICH COMPRISES SECURING IN THE AREA WHERE SAID FLOOR IS TO BEFORMED AN OUTER MEMBER WHICH IS OPEN AT ITS TOP, PLACING WITHIN SAIDOUTER MEMBER AN INNER MEMBER HAVING AN OPEN TOP AND COMPRISING SIDEWALLS, A BOTTOM WALL, AND AN OUTWARDLY EXTENDING FLANGE AT THE UPPERPORTION THEREOF, SAID SIDE WALLS BEING FREELY TELESCOPICALLY RECEIVABLEINSIDE SAID OUTER MEMBER, SAID FLANGE EXTENDING RADIALLY OUTWARDLYBEYOND THE RADIALLY INNER SURFACE OF SAID OUTER MEMBER AND RESTING ONTHE UPPER EDGE OF SAID OUTER MEMBER, POURING CONCRETE OVER SAID AREAROUND SAID OUTER MEMBER AND INSIDE SAID INNER MEMBER, PERMITTING SAIDCONCRETE TO SET, REMOVING SAID INNER MEMBER, TOGETHER WITH THE CONCRETECORE FORMED THEREWITHIN, FROM SAID OUTER MEMBER, AND REMOVING SAID COREFROM SAID INNER MEMBER.